<template>
  <div>
    <hr>
    <h4>父组件:{{ num }}---{{ num2 }}</h4>
    <hr>
    <Son v-model="num" @input="val=>num=val" />
    <Son :aaa.sync="num2" />
  </div>
</template>

<script>
import Son from './Son.vue'
export default {
  components: { Son },
  data() {
    return {
      num: 100,
      num2: 200
    }
  }
}
</script>

<style>

</style>
